Container closure



April 2, 1946- H. 4A.- BARNBY -r AL 2,397,589

CONTAINER CLOSURE Filed May l, 1945 WAX OILPAPER ADHESIVE KRAFT PAPER ADHESIVE 'UTE ADHESIVE KRAFT PAPER Patented Apr. 2, 1946 www.

UNITED STATES PATIEINT i)FFI(1l-1fA CONTAINER CLOSURE Herbert A. Barnby and Jack M. Wheaton, Toledo,

Ohio, assgnors to Owens-Illinois Glass Company, a corporation of Ohio Application May 1, 1943, Serial No. 485,320 4 claims. (c1. zie-3s) Our invention relates to caps or closures for jars, bottles and other containers. An object of the invention is to provide a novel and practical cap for closing and hermetically sealing a container to' which it is applied. The invention provides a cap which is particularly adapted for use With jars or other'containers in which foodstuis are packed and sealed by processes which result in forming a partial vacuum within'thje container. Such a vacuum process is extensively used in canning fruits, vegetables, and the like, in which process the jars are filled and the caps applied while the material is at a high temperature, so that as the contents of the jar cools, the steam or vapor is condensed and produces a partial vacuum.

An object of our invention is to provide a cap which is readily applied to the jar and makes an effective and permanent seal.

A further object of the invention is to provide a cap of the character indicated which is adapted for use with various styles of jar tops or 1inishes, and which does not require any special fastening means for securing the cap` A further object of the invention is to provide such a cap which may be readily and repeatedly applied to and seal the container independently of any vacuum, so that when only a part of the contents is dispensed atY a time, the remaining portion may be resealed until needed.

A further object of the invention is to provide a cap or closure of the character indicated which is made of inexpensive materials which are readily available and which serve as an eiiicient substitute for the usual metal caps.

Other objects of the invention will appear hereinafter.

Referring to the accompanying drawing:

Fig. 1'is a fragmentary sectional elevation of a glass jar with a cap placed in position thereon.

Fig. 2 is a similar view but with the cap bowed downwardly owing to the partial vacuum within the jar.

Fig. 3 is a View similar to Fig. 2, but with the thickness of the various layers of material forming the cap, greatly exaggerated for the purpose of illustration.

Fig. 4 is a fragmentary view on a larger scale, of a portion of the cap as applied to the jar.

Fig. 5 is a diagrammatic plan View of the cap with the layers of material progressively broken away.

The closure device or cap C is shown applied to a glass jar J having a neck 6 formed with an rial bonded together by layers of adhesive.

external spiral bead or screw thread "Iy adapting the jar for use with a screw-threaded cap or ring.

The cap is of laminated construction comprising superposed layers or disks of suitable mate- The cap as shown has an inner layer II` of wax, applied to the under surface of a layer ordisk of oil paper I2, alayer of'pulpboard I4 overlying the disk I2 and secured .thereto by an interposed layer I3 of adhesive material, a layer i6 ofykraft paper or the like overlying the pulpboard and bonded thereto by a layer I5 of adhesive. The uppermost section. or layer of the cap provides a -cap shell which comprises a disk2 of kraft paper or the like formed with a. skirt 2| which surrounds the subjacent laminationsandV extends downwardly into position to surround the bead l, such bead serving to hold the capcenterecl on the jar. An inner layer I8 of jutepaper is bonded to the kraft paper 20 by an interposed layer I9 of adhesive and provides a `lining for the cap shell.` A layer il of adhesive material is provided between the laminations I8 and I6. It will4 be seen that the laminations comprised in the cap are bonded together by adhesive in a manner to form an integral or lone-piece cap.

The layer tI is a sealing material. preferably of an amorphous petroleum wax, which atv the temperatures to whichit is subjected during the vacuum sealing operations', `is of a consistency adapting it to making an effective seal, and'which at normal living room temperatures remains sufficiently soft and plastic to make a good seal when applied with aslight pressure to the container. The cap is thus adapted to be repeatedly applied to the container and make an airtight seal when applied at normal living room temperatures. The petroleum wax may have added thereto, a small percentage of any suitable viscous material whichincreases the adhesive qualities of the wax and prevents crystallization at low temperatures. We have found that a small percentage of the commercial product known as Vistac'Nd 2" added to the petroleum wax is satisfactory for this purpose, such product being a synthetic hydrocarbon of the polybutene type having a molecular weight of approximately 6000.

The layer I2 of oil paper, being nonporous and impervious to moisture, cooperates with the layer Il of Wax to make a reliable and permanent seal. The disk I4, preferably consisting of a iirm pulpboard of substantially greater thickness than the adjoining layers of paper, serves to stiffen and strengthen the cap as -a inch gives satisfactory results. The kraft paper lamination I B is comparatively thin but provides a strong, tough, iexibleV layer which greatly adds to the strength of the cap.

The cap shell which comprises the kraft paper 20 and its inner lining I8 of jute bonded thereto by the layer I9 of adhesive, serves to Strengthen the cap as a whole ancljincrease'sits resistance to bending stresses.v It oiers effective resistance to the bowing downward of the cap under atmospheric'pressure when a partial vacuum is formed within the container, and thus prevents excessive deformation or bowing of the cap.-

ModificationsY may be resorted'to withinthe spirit and scope of our invention. f

We claim:

1. A cap for closing and sealing a container, y

comprising superposed laminations including an inner layerV of wax which is soft and plastic at lamination of oil paper, a lamination of pulpboard overlying the oil paper and :bonded therepaperand'the cap as a Whole being sufllciently 'soft and Vflexible to permit a-substantial downward iiexing or bowing under atmospheric pressure when the cap is seated on and sealed to a vacuumized container.

2. Arcap for closing andY sealing a container,

Y comprising superposed laminations including an inner layer of wax which-is Soft and vplastic at normal livingroom temperatures, a superposed lamination of `oil paper, .a lamination of pulpi v20 normal living room temperatures, a 'superposed' board overlying'the oil paper and bonded there- Y toY by a layer of adhesive material, a cap shell overlyingthe pulpboard and formed with a marginal skirt Ysurrounding'said laminations and extending downwardly therebelow, and means for bonding said shell to the pulpboard, the pulpboard lamination being of greater thickness than they adjoining layers'of papen and the cap asa whole being sucientlysoft and flexible to permit a substantial downward flexing of the cap under atmosphericV pressure' 'whenv the cap isy adjoining layers of Ypaper of substantially less Y Y 2,397,589 whole. Vwehave found that a thickness or .05

seated on the vacuumized container, said shell comprising an outer layer of kraft paper, an inner lining of'jute paper, and a layer of adhesive bonding said jutepaper to the kraft paper,

y said shell providing means for strengthening the cap and eiectively limiting theV degree of said downward flexing.

3.,A cap for closing and sealing a container, comprising superposed laminations including an inner layer of wax which is soft and-plastic at ,normal living room temperatures, a superposed lamination of oil paper, a lamination of pulpboard overlying the oil paper and bonded thereto by a layer of adhesive material,and a cap shell comprising alsheet of kraft paper overlying the pulpboard and formed with a marginal skirt surrounding said laminations and extending downwardly'therebelow, a lamination of kraft paper interposed between said pulpboard and the cap shell, and layers of adhesive material interposed between and bonding together the pulpboard and said lamination of kraft paper and between and bondingrtogether the said kraft paper and said cap shell, the thickness of the pulpboard lamination being of the order of .05

inch and the adjoining layers of paper kof sub-v stantially less .thickness than the pulpboard, the cap as a whole being fortified by the cap shell Y against excessive deformation or bowing when subjected to the -suctional action of a partial vacuum within the container.A

V4. A cap providing aA closure for containers, said cap being of laminated construction cornprising superposed laminations consistingrespectively of kraft paper, jute paper, kraft paper, pulpboard, and oil paper in the order mentioned, with interposed layers of adhesive material'between said laminations `and bondingthem together, the outer lamination of kraft paperserv-r ing as a cap shell and being` formed with an integral marginal skirt surrounding Said other laminations, the thickness of the' pulpboard lamination being of the order of .05 inch and the thickness than'the pulpboarfLthe cap as a whole being fortified by the cap Shell against excessive kdeformation or bowingrwhen Vsubjected to the suctional action of a partial' vacuum within' the container. Y

Y HERBERT A. BARNBY.

JACK WHEATON. 

